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Somersetite, Pb8O(OH)4(CO3)5, a new complex hydrocerussite-related mineral from the Mendip Hills, England

Published online by Cambridge University Press:  15 May 2018

Oleg I. Siidra*
Affiliation:
Department of Crystallography, St Petersburg State University, University Embankment 7/9, 199034 St Petersburg, Russia Nanomaterials Research Center, Kola Science Center, Russian Academy of Sciences, Apatity, Murmansk Region, 184200, Russia
Diana O. Nekrasova
Affiliation:
Department of Crystallography, St Petersburg State University, University Embankment 7/9, 199034 St Petersburg, Russia
Rick Turner
Affiliation:
The Drey, Allington Track, Allington, Salisbury SP4 0DD, Wiltshire, UK
Anatoly N. Zaitsev
Affiliation:
Department of Mineralogy, St. Petersburg State University, University Embankment 7/9, 199034 St Petersburg, Russia Core Research Laboratories, Imaging and Analysis Centre, Natural History Museum, Cromwell Road, London SW7 5BD, UK
Nikita V. Chukanov
Affiliation:
Institute of Problems of Chemical Physics, Chernogolovka, Moscow region, 142432, Russia
Yury S. Polekhovsky
Affiliation:
Department of Mineral Deposits, Faculty of Geology, St. Petersburg State University, University Embankment 7/9, St. Petersburg 199034, Russia
John Spratt
Affiliation:
Core Research Laboratories, Imaging and Analysis Centre, Natural History Museum, Cromwell Road, London SW7 5BD, UK
Mike S. Rumsey
Affiliation:
Mineral and Planetary Sciences Division, Earth Sciences Department, Natural History Museum, Cromwell Road, London SW7 5BD, UK
*

Abstract

The new mineral somersetite, has been found at Torr Works (‘Merehead quarry’) in Somerset, England, United Kingdom. Somersetite is green or white (typically it is similar visually to hydrocerussite-like minerals but with a mint-green tint), forms plates and subhedral grains up to 5 mm across and up to 2 mm thick. In bi-coloured crystals it forms very thin intergrowths with plumbonacrite. The empirical formula of somersetite is Pb8.00C5.00H4.00O20. The simplified formula is Pb8O(OH)4(CO3)5, which requires: PbO = 87.46, CO2 = 10.78, H2O = 1.76, total 100.00 wt.%.

The infrared spectrum of somersetite is similar to that of plumbonacrite and, to a lesser degree, hydrocerussite. Somersetite is hexagonal, P63/mmc, a = 5.2427(7), c = 40.624(6) Å, V = 967.0(3) Å3 and Z = 2. The eight strongest reflections of the powder X-ray diffraction (XRD) pattern [d,Å(I)(hkl)] are: 4.308(33)(103), 4.148(25)(104), 3.581(40)(107), 3.390(100)(108), 3.206(55)(109), 2.625(78)(110), 2.544(98)(0.0.16) and 2.119(27)(1.0.17). The crystal structure was solved from single-crystal XRD data giving R1 = 0.031. The structure of somersetite is unique and consists of the alternation of the electroneutral plumbonacrite-type [Pb5O(OH)2(CO3)3]0 and hydrocerussite-type [Pb3(OH)2(CO3)2]0 blocks separated by stereochemically active lone electron pairs on Pb2+. There are two blocks of each type per unit cell in the structure, which corresponds to the formula [Pb5O(OH)2(CO3)3][Pb3(OH)2(CO3)2] or Pb8O(OH)4(CO3)5 in a simplified representation. The 2D blocks are held together by weak Pb–O bonds and weak interactions between lone pairs.

Type
Article
Copyright
Copyright © Mineralogical Society of Great Britain and Ireland 2018 

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Footnotes

Associate Editor: Juraj Majzlan

References

Anthony, J.W., Bideaux, R.A., Bladh, K.W. and Nichols, M.C. (2003) Handbook of Mineralogy. V. Borates, Carbonates, Sulfates. Mineral Data Publishing, Tucson, USA.Google Scholar
Brese, N.E. and O'Keeffe, M. (1991) Bond-valence parameters for solids. Acta Crystallographica. B47, 192197.Google Scholar
Britvin, S.N., Dolivo-Dobrovolsky, D.V. and Krzhizhanovskaya, M.G. (2017) Software for processing the X-ray powder diffraction data obtained from the curved image plate detector of Rigaku RAXIS Rapid II diffractometer. Proceedings of the Russian Mineralogical Society, 146, 104107.Google Scholar
Giuseppetti, G., Mazzi, F. and Tadini, C. (1990) The crystal structure of leadhillite: Pb4(SO4)(CO3)2(OH)2. Neues Jahrbuch für Mineralogie Monatshefte, 1990, 255268.Google Scholar
Ibáñez-Insa, J., Elvira, J.J., Llovet, X., Pérez-Cano, J., Oriols, N., Busquets-Masó, M. and Hernández, S. (2017) Abellaite, NaPb2(CO3)2(OH), a new supergene mineral from the Eureka mine, Lleida province, Catalonia, Spain. European Journal of Mineralogy, 29, 915922.Google Scholar
Krivovichev, S.V. and Brown, I.D. (2001) Are the compressive effects of encapsulation an artifact of the bond valence parameters? Zeitschrift für Kristallographie – Crystalline Materials, 216, 245247.Google Scholar
Krivovichev, S.V. and Burns, P.C. (2000) Crystal chemistry of basic lead carbonates. II. Crystal structure of synthetic ‘plumbonacrite’. Mineralogical Magazine, 64, 10691075.Google Scholar
Krivovichev, S.V., Turner, R., Rumsey, M., Siidra, O.I. and Kirk, C.A. (2009) The crystal structure of mereheadite. Mineralogical Magazine, 73, 7589.Google Scholar
Krivovichev, S.V., Mentré, O., Siidra, O.I., Colmont, M. and Filatov, S.K. (2013) Anion-centered tetrahedra in inorganic compounds. Chemical Reviews, 113, 64596535.Google Scholar
le Page, Y. (1987) Computer derivation of the symmetry elements implied in a structure description. Journal of Applied Crystallography, 20, 264269.Google Scholar
Martinetto, P., Anne, M., Dooryhée, E., Walter, P. and Tsoucaris, G. (2002) Synthetic hydrocerussite, 2PbCO3·Pb(OH)2, by X-ray powder diffraction, Acta Crystallographica, C58, i82i84.Google Scholar
Olby, J.K. (1966) The basic lead carbonates. Journal of Inorganic Nuclear Chemistry, 28, 25072512.Google Scholar
Palache, C., Berman, H. and Frondel, C. (1951) The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana. Volume II. John Wiley and Sons, New York.Google Scholar
Pouchou, J.L. and Pichoir, F. (1991) Quantitative analysis of homogeneous or stratified microvolumes applying the model “PAP”. Pp. 3175 in: Electron Probe Quantification, (Heinrich, K.F.J. and Newbury, D.E., editors). Plenum Press, New York.Google Scholar
Pyykö, P. (1997) Strong closed-shell interactions in inorganic chemistry. Chemical Reviews, 97, 597636.Google Scholar
Rumsey, M.S., Krivovichev, S.V., Siidra, O.I., Kirk, C.A., Stanley, C.J. and Spratt, J. (2012) Rickturnerite, Pb7O4[Mg(OH)4](OH)Cl3, a complex new lead oxychloride mineral. Mineralogical Magazine, 76, 5973.Google Scholar
Sheldrick, G.M. (2015) New features added to the refinement program SHELXL since 2008 are described and explained. Acta Crystallographica, C71, 38.Google Scholar
Siidra, O.I., Krivovichev, S.V. and Filatov, S.K. (2008 a) Minerals and synthetic Pb(II) compounds with oxocentered tetrahedra: review and classification. Zeitschrift für Kristallographie – Crystalline Materials, 223, 114126.Google Scholar
Siidra, O.I., Krivovichev, S.V., Turner, R. and Rumsey, M. (2008 b) Chloroxiphite Pb3CuO2(OH)2Cl2: structure refinement and description in terms of oxocentered OPb4 tetrahedra. Mineralogical Magazine, 72, 793798.Google Scholar
Siidra, O.I., Britvin, S.N., Krivovichev, S.V., Klimov, D.A. and Depmeier, W. (2014) Crystallography between Kiel and St. Petersburg: review of collaboration and the crystal structure of [Tl5(SiO4)(OH)]2[Tl6(SO4)(OH)4]. Zeitschrift für Kristallographie – Crystalline Materials, 229, 753759.Google Scholar
Siidra, O.I., Nekrasova, D.O., Depmeier, W., Chukanov, N.V., Zaitsev, A.N. and Turner, R. (2018 a) Hydrocerussite-related minerals and materials: structural principles, chemical variations and infrared spectroscopy. Acta Crystallographica B, 74, 182195.Google Scholar
Siidra, O.I., Nekrasova, D.O., Chukanov, N.V., Pekov, I.V., Yapaskurt, V.O., Katerinopoulos, A., Voudouris, P., Magganas, A. and Zaitsev, A.N. (2018 b) Hydrocerussite- related phase NaPb5(CO3)4(OH)3 from the ancient slags of Lavrion, Greece. Mineralogical Magazine, 82, 809819.Google Scholar
Siidra, O.I., Jonsson, E., Chukanov, N.V., Nekrasova, D.O., Pekov, I.V., Depmeier, W., Polekhovsky, Y.S. and Yapaskurt, V.O. (2018 c) Grootfonteinite, Pb3O(CO3)2, a new mineral species from the Kombat mine, Namibia, merotypically related to hydrocerussite. European Journal of Mineralogy, 30, 383391.Google Scholar
Spek, A.L. (2003) Single-crystal structure validation with the program PLATON. Journal of Applied Crystallography, 36, 713.Google Scholar
Steele, I.M., Pluth, J.J. and Livingstone, A. (1998) Crystal structure of macphersonite Pb4SO4(CO3)2(OH)2: comparison with leadhillite. Mineralogical Magazine, 62, 451459.Google Scholar
Steele, I.M., Pluth, J.J. and Livingstone, A. (1999) Crystal structure of susannite, Pb4SO4(CO3)2(OH)2: a trimorph with macphersonite and leadhillite. European Journal of Mineralogy, 11, 493499.Google Scholar
Symes, R.F., Cressey, G., Criddle, A.J., Stanley, C.J., Francis, J.G. and Jones, G.C. (1994) Parkinsonite, (Pb,Mo,◻)8O8Cl2, a new mineral from Merehead quarry, Somerset. Mineralogical Magazine, 58, 5968.Google Scholar
Turner, R. (2006) A mechanism for the formation of the mineralized Mn deposits at Merehead Quarry, Cranmore, Somerset, England. Mineralogical Magazine, 70, 629655.Google Scholar
Turner, R.W. and Rumsey, M.S. (2010) Mineral relationships in the Mendip Hills. Journal of the Russell Society, 13, 347.Google Scholar
Turner, R.W., Siidra, O.I., Krivovichev, S.V., Stanley, C.J. and Spratt, J. (2012) Rumseyite, [Pb2OF]Cl, the first naturally occurring fluoroxychloride mineral with the parent crystal structure for layered lead oxychlorides. Mineralogical Magazine, 76, 12471255.Google Scholar
Turner, R.W., Siidra, O.I., Rumsey, M.S., Polekhovsky, Y.S., Kretser, Y.L., Krivovichev, S.V. and Spratt, J. (2015) Yeomanite, Pb2O(OH)Cl, a new chain-structured Pb oxychloride from Merehead Quarry, Somerset, England. Mineralogical Magazine, 79, 12031211.Google Scholar
Welch, M.D., Cooper, M.A., Hawthorne, F.C., Criddle, A.J. (2000) Symesite, Pb10(SO4)O7Cl4(H2O), a new (PbO)-related sheet mineral: description and crystal structure. American Mineralogist, 85, 15261533.Google Scholar
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